Can smoke receive shadows in Eevee on 2.8?
It actually is working in your file, but with such wide spot lights it's invisible/too subtle to see. As you can see, even with cycles it's not visible:



This is because there's still plenty of light being scattered from behind and in front of the object's shadow; in comparison the amount of light being blocked becomes insignificant:



If you add a larger object, casting a larger shadow, you can start to see the effect. Narrowing the light cone also works.

However, you may run into problems with the shadow resolution being too low, especially with small objects. Make sure the global shadow resolution is sufficient in Properties > Render > Shadows:



Other common problematic shadow settings are the Clip Start on the lamp's shadow settings (make sure that isn't too large) and too much Softness, which can eat narrow shadows (like those cast by text). With 0 softness you get nice crisp text shadows: